Method of and means for installation of a crankcase ventilating system



Jan. 4-, 1966 w. DAUBNER ETAL 3,227,010

METHOD OF AND MEANS FOR INSTALLATION OF A CRANKCASE VENTILATING SYSTEM Filed Aug. 13, 1965 2 Sheets-Sheet 1 .i5- 45 W W 14 11 a5 i I m J 16 V g r ill! INVENTORS WILLIAM L. DAUBNER 54 w. LOWTHER Wig/m5??? Jan. 4, 1966 w. L. DAUBNER ETAL 3,227,010

METHOD OF AND MEANS FOR INSTALLATION OF A CRANKCASE VENTILATING SYSTEM Filed Aug. 13, 1965 2 Sheets-Sheet 23 Q r\ Z9 I38 k 47 5% V I v s s 5:57 i E =LEINVENTORS WILLIAM L. DAU NER \Al!{ LFRED W. LOW HER W i Q ditty.

United States Patent 3,227,010 METHDD 6F AND MEANS FGR INfiTALLATION OF A CRANKQASE VENTILATING SYSTEM William L. Daubner, Hartford, Win, and Wilfred W.

Lowther, Downers Grove, Ill., assignors to Midas InternationalCorperation, Chicago, 111., a corporation of Illinois i Filed Aug. 13, B63, Ser. No. 301,813

Claims. (Cl. 77-5) This invention relates to improvements in crankcase ventilation systems and to the steps of the method of installation of such a system and tools employed in practicing the method.

Vehicle internal combustion engines are equipped with abreather tube and a road draft tube both in communication with the crankcase to afford ventilation of the crankcase. The efliciency of these tubes is nominal primarily because there is insufficient draft generated while the vehicle is travelling at less than about 30 mph, consequently there is maximum condensation, dilution of the crankcase oil and sludge formation while running at low speeds. At all times there is a discharge of blow-by gases and fumes into atmosphere. The crankcase ventilation system herein disclosed is what might be termed a closed ventilation system because all blow-by gases and fumes normally deposited in the crankcase and discharged to atmosphere are evacuated from the crankcase by vacuum before they can condense, form sludge or cause dilution of the crankcase oil. ing the highest available point of the crankcase with the intake manifold by a conduit that includes a pressure regulating valve which functions at all engine speeds. In all instances, the road draft tube and breather tube are blocked off and atmosphere is admitted into the crankcase through the air cleaner. This provides a closed ventilation system wherein all gases, fumes, etc. within the crankcase are drawn into the intake manifold for mixture with the incoming gas-air mixture from the carburetor and are consumed,

Various systems, of varying degrees of efiiciency, have been adopted to accomplish the general results but such systems as are known are not closed systems and their installation requires extensive dismantling of the engine accessories, replacement of parts and the insertion of expensive fixtures. For example, one known system necessitates the removal of the rocker-arm cover or tappet cover for the drilling of a hole therethrough and removal of the carburetor and insertion between the carburetor and manifold of an adapter having the requisite conduit connector. Such removal and replacement of the carburetor involves considerable labor in the re-adjustment of the carburetor control linkage, insertion of longer bolts or studs and the installation of new gaskets. When the rocker-arm cover or tappet cover is replaced, a new gasket must be inserted. Also, in such known installations the road draft tube must be replaced with an adapter. All this is time consuming and costly. No effort has been made to connect the conduits directly through the wall of the intake manifold, or through the rocker-arm cover without emoving same, primarily because of the danger of chips falling into the interiors thereof with resultant damage to the engine.

Applicants have overcome the likelihood of chips falling into the interior of the engine and consequently are now able to make connections directly with the manifold and with the mounted rock-arm cover, thus avoiding the need for extensive part removal and replacement, road draft tube adapter installation and readjustment of the carburetor control linkage, More particularly, zapplicants employ a novel .approach'to the problem of chip displacement through the generation of high air pressure This is accomplished by connect- 3,227,010 Patented Jan. 4:, 1966 within the engine during the drilling operations. As a result, as soon as the cutting tool breaks through the wall being apertured, the escape of high pressure air outwardly through the opening entrains all chips then present and generated during the remaining drilling operation.

Pressurization of the engine is accomplished by initially plugging the road draft tube and breather tube and removing the air cleaner from the carburetor throat. No other parts are removed. A fixturehaving an air line connection is temporarily secured firmly over the carburetor throat and a fixture having an air lineconnection is placed in the breather tube or oil fill opening. An air pressure line from any suitable air compressor system commonly found in garages and repair shops is connected to the air line connection on the breather tube or oil fill opening and an internal engine pressure of about 45 pounds per square inch is maintained within the crankcase and connecting areas during subsequent drilling. The air line then is connected to the fixture on the carburetor throat and while maintaining a pressure of about 45 pounds per square inch in the manifold, an opening is drilled in said manifold. In instances where it is necessary. to cut a relatively large hole in the rocker-arm cover, a specially designed hole saw preferably is employed which utilizes the pressure flow of air through the opening performed to entrain all chips from the region of the opening.

It is therefore an object of this invention it provide a novel method for cutting openings in the wall of aclosed chamber,

Another object is to provide a novel method for entraining all chips from within and around an opening being cut in a wall of a closed chamber.

Another object is to provide novel means for quickly, easily and inexpensively installing .a ventilating system for an internal combustion engine.

The structure and method by means of which the above noted and other advantages and objects of the invention are attained will be described in the following specification, taken in conjunction with the accompanying drawings, showing a preferred illustrative embodiment of the invention, in which:

FIG. 1 is an elevational view of an internal combustion engine'having the closed crankcase ventilation system of the present invention installed thereon.

FIG. 2 is a schematic sectional view of an internal combustion engine equipped with the system.

FIG. 3 is a view, partly in section, showing the installation of a temporary fixture on the carburetor during the installation of the system.

FIG. 4 is a fragmentary sectional detail view of the conduit connection with'the rocker-arm cover.

FIG. 5 is a detail sectional View of a conduit and backfire screen connection with the air cleaner.

FIG. 6 is a detail sectional view of the flow control valve, mounted in the intake manifold.

FIGS. 7 through 11 are sectional detail views of the manifold wall showing successive progress steps of the drill bit used to provide ahole therein.

I FIG. 12 is a sectional view of the hole saw, showing it about to cut the wall of the rocker-arm cover.

FIG. 13is a fragmentary view similar to FIG. 12, but on an enlarged scale, showing the rocker-arm cover penetrated.

FIG. 14 is a detail sectional view showing installation of a temporary fixture in the oil fill opening on the rockerarm cover.

Referring to the accompanying drawings and particularly to FIG. 1, the internal combustion engine 11 illustrated is a Chevrolet 6-cylinder engine having overhead rocker arms enclosed in -a rocker-arm cover 12. As is well understood, and as shown in FIG. 2, the space o enclosed by the rocker-arm cover is in flow communication with the crankcase 13 so as to afford ventilation of the interior of the cover. Future reference herein to the crankcase will include all space in communication with the crankcase proper. In this disclosure, the rocker-arm cover has an oil fill opening 14 that normally is capped with a breather cap (not shown). Also, the crankcase is provided with the usual road draft tube 15, which normally serves to discharge blow-by gases and fumes into atmosphere. Mounted on the engine block is the usual intake manifold 16, having a carburetor 17 in flow communication therewith and upon which is arranged an air cleaner 18.

Still referring to the FIG. 1 disclosure, means is provided for sealing the normal ventilating openings in the crankcase and affording a passageway for conveying blow-by gases and fumes from the crankcase into the intake manifold 16 where they are mixed with the incoming gas-air mixture from the carburetor and consumed during engine operation. As illustrated, a flexible conduit 19 is connected at one of its ends in flow communication With the interior of the rocker-arm cover. In the 'present disclosure this connection is made through a special adaptor 21 that replaces the usual breather cap fitted into oil fill opening 14. The other end of said conduit 19 is connected in flow communication with the intake manifold preferably as close to the carburetor as physically possible. A flow control valve 22, described presently, is arranged in the conduit at its connection with the intake manifold.

In order to admit atmosphere into the crankcase to ventilate same, there is provided a conduit 23 which, in this instance, is connected at one end to the rocker-arm cover 12 and at its other end to the air cleaner 11-3. The specific manner and method of making the connections with the manifold, air cleaner and rocker-arm cover will be described presently.

The system operates to cause all blow-by gases and fumes to be drawn out of the crankcase and replaced by clean atmospheric air entering through conduit 23. The withdrawn gases are discharged into the intake manifold 16 and are burned in the cylinders. In operation, the intake through the air cleaner decreases as the relative vacuum in the intake manifold increases, and vice versa.

The, provision of two conduits 19, 23, on the crankcase,

one from the air cleaner and the other to the intake manifold insures both ventilation of the crankcase and the return of all blow-by gases and fumes to the engine cylinders via the intake manifold. This closed ventilation system functions to prevent dilution of crankcase oil, creation of sludge, and generally improves engine performance but, more important, it eliminates the prior practice of discharging blow-by gases and smog producing chemicals into the atmosphere.

The various connections with the manifold, air cleaner and rocker-arm cover and the means for gaining entry into these arts will now be described.

As previously noted hereinabove, in the installation illustrated, no special problem is involved in connecting the conduit 19 to the rocker-arm cover. This connection involves the use of a bayonet type adaptor 21 having a nipple 24 thereon over which the related end of conduit 19 is telescoped. This adaptor is devoid of breather holes such as are present in the usual breather cap which is replaced thereby. The other end of conduit 19 is connected to the control valve 22 best shown in FIG. 6. This valve is fully disclosed and claimed in a copending application Serial No. 164,718, filed January 18, 1962, by Wilfred W. Lowther, and is not claimed in this application.

The valve illustrated comprises a tubular body 25 externally threaded at one end, as at 26, and provided at its other end with a nipple 27 over which one end of conduit 19 is fitted. The valve includes a floating valve element 2% supported by a coil spring 29 so as to be responsive to internal negative pressures in the intake manifold to which it is connected for regulating the flow of blow-by gases therethrough. Briefly, when the engine is not operating, the valve element is in the elevated position shown. When the engine is operating, the position of the valve element 28 varies with intake manifold vacuum so as to control negative pressure in conduit 19, in inverse proportion to the degree of vacuum in the manifold through positioning of the tapered portion 28a of valve element 28 relative to the orifice 22a in the valve body. The valve therefore allows a carefully metered amount of blow-by gases and fresh air to chew late through the crankcase and into the intake manifold in direct proportion to the amount of blow-by gases produced by the engine.

As noted hereinabove, valve 22 is mounted directly on the intake manifold. This requires that a hole be drilled and tapped in the wall manifold 16. Heretofore, this has been impossible of accomplishment without removing the manifold from the engine so that it could be cleaned of chips after the drilling. Applicants drill and tap this hole without removing the manifold and without the danger of chips falling into the interior thereof by the herein disclosed method now to be described.

Following removal of the air cleaner, a special fitting 32 (FIG. 3) is fitted over the air intake throat 33 of the carburetor 1'7 and the carburetor is opened to full throttle position. The fitting may comprise a cupshaped body having a clamp 34 on its lower open end for securement tightly about the carburetor throat. A nipple 35 is carried by said fitting for connection with an air hose 36 having an air pressure regulator therein and connected to the usual air pressure source ordinarily found in repair shops and garages. Air then is admitted into the intake manifold to maintain an internal pressure of about 45 pounds per inch. Drilling of the necessary hole in the intake manifold may now be started.

It has been found most satisfactory to use a drill bit 37 of the kind shown in FIG. 7, mounted in a slow speed electric drill. As illustrated, this bit has a small diameter starting point 33 which gradually enlarges as at 39 and terminates in a sharply tapered shoulder 41 that merges with its larger diameter 42. The two flutes 43 (one shown) therein extend from the tip of point 38 into the larger diameter 42.

This type of bit generates fine chips as distinguished from flaking as ordinarily occurs when drilling through cast iron. It preferably is modified slightly by chamfering its edge, as at 43a so as to minimize the breakthrough effect, although it will function for the purpose intended without such modification.

Referring now to FIGS. 71 1, FIGURE 8 illustrates the position of the bit 37 during initial drilling. In FIG. 9, the tip 38 has penetrated through the manifold wall. When this break through occurs the internal pressure within the manifold generates sharp air jet streams up through the flutes entraining all chips outwardly. As the drilling progresses, the chips continue to be entrained in the jet streams issuing along the flutes. In this mannor there is no possibility of any chips entering the manifold. The internal pressure is maintained during the tapping operation, the chips being flowed out of the opening by air jet streams generated in the usual slots of the tapping tool. The valve 22 may now be threaded into the tapped hole in the manifold.

Cutting of a hole in the rocker-arm cover for connecting the conduit 23 with the interior of the crankcase embodies the same principal except that a hole saw of the kind disclosed in FIGS. 12 and 13 is used. Prior to using this hole cutter, the road draft tube 15 is permanently closed as for example by means of a plug 44 (FIG. 1). The breather cap is removed from the oil fill opening 14 and a temporary fixture 45 (FIG. 14) having an air line connector is mounted in the opening and the air hose 36 from the compressor is connected to it. This completely seals the crankcase except for possible minor leaks in the system and which are of no consequence, Air then is admitted into the crankcase through this fixture so as to maintain an internal crankcase pressure of about 45 pounds per inch. The drilling of the crankcase hole may now be started.

As shown in FIG. 12, the hole saw comprises the usual circular saw 46 which has relatively deep cutting teeth 47 on the edge of its circular wall and which is mounted in a slow speed drill. The commercial hole saw has peripheral apertures 48 therein which preferably are, but necessarily need not be, closed. In order to close these apertures, a sleeve 49 is telescoped over the hole cutter prior to its being mounted in the drill. This sleeve preferably has an external flange 51 spaced upwardly from cutting teeth 47 and which functions to limit pass through of the saw when the hole is cut.

The hole saw is also fitted with a center bit 52 used to start and guide the cutting operation. As best shown in FIG. 12, the bit 52 initially cut a centering hole in the wall of rocker-arm cover 12. As soon as this bit penetrates the wall, jet streams of air from within the rocker-arm cover entrain the chips outwardly into the interior of the hole saw and then outwardly radially through the gaps between the teeth 47. When the hole saw starts its cut, the chips generated tend to collect on the outside surface of the rocker-arm cover wall but owing to the jet streams flowing out around the center bit, these chips also are entrained in the air streams and are blown outwardly radially through the spaces between the cutting teeth 47, thus there is no accumulation of :chips on the surface of the slug being cut from the wall. As the hole saw cuts through the wall (FIG. 13) the chips generated are likewise blown outwardly and radially. Also, the cut disk or slug 53 is held in the hole saw by the internal pressure within the rocker-arm cover and is removed when the cutter is withdrawn.

When the hole is performed, a grommet 54 (FIG. 4) is inserted therein and a fitting nipple 55 is inserted in the grommet and held firmly thereby. One end of conduit 23 then is telescoped over the fitting. The special fixture 45 can now be removed from the oil fill opening and an adapter 21 (FIG. 1) is connected in said opening to afford a flow connection for conduit 19.

A similar hole is cut in the air cleaner wall but because the air cleaner has been or can be removed from the carburetor it is not pressurized and any chips entering same are easily removed by subsequent air blast. As shown in FIG. 5, this hole is fitted with a grommet 56 through which a conduit fitting 57 having a backfire screen 58 thereon is extended. The other end of conduit 23 is connected to this fitting.

If it has not been earlier removed, the fixture 32 (FIG. 3) can now be removed and the air cleaner replaced. It may be and usually is necessary to re-adjust the carburetor mixing valve to compensate for the blow-by gases returned to the manifold.

It should be apparent that applicants have provided a new method for installing a crankcase ventilating system which requires but a minimum of dismantling of the engine and which may be installed with minimum labor and at nominal expense all without danger of the deposit of metallic chips into the interior of the crankcase or intake manifold. Also, although applicants have illustrated a specific installation, the system may embody variations in the exact location of the various conduits and connections to adapt the system to engines of different types and makes.

Although we have described a preferred embodiment of the invention in considerable detail, it will be understood that the description thereof is intended to be illustrative, rather than restrictive, as many details of the structure disclosed may be modified or changed and the steps of the method may be varied without departing from the spirit or scope of the invention. Accordingly, we do not desire to be restricted to the exact construction, method and means specifically described.

We claim:

1. The steps of the method for installing a crankcase ventilating system in an internal combustion engine equipped with a carburetor and an air intake manifold which comprises placing a fixture over the carburetor air inlet, connecting an air line to said fixture, delivering pressurized air into the interior of the manifold through said fixture, and drilling a hole in the wall of said intake manifold, said internal pressure ejecting all drill chips from said hole.

2. The steps of the method of installing a crankcase ventilating system in an internal combustion engine having an intake manifold, a carburetor and an air cleaner; which comprises removing the air cleaner, connecting a conduit fitting to the carburetor air inlet, connecting a conduit to said fitting and to a source of pressurized air, drilling a hole in the manifold while air is maintained under pressure in said manifold, said air being expelled through the opening during the drilling operation so as to entrain all drill chips.

3. The steps of the method of installing a crankcase ventilating system in an internal combustion engine having an intake manifold and a carburetor equipped with an air cleaner which consists of removing the air cleaner, placing a cover having a conduit fitting over the carburetor air inlet, connecting a conduit to said conduit fitting, delivering air of predetermined high pressure into the interior of the manifold, through said conduit and fitting to maintain the manifold pressurized, and drilling a hole in the wall of said intake manifold, said internal pressure ejecting all drill chips from said hole.

4. The steps of the method for installing a crankcase ventilating system in an internal combustion engine of a type having rocker arms and a cover thereover provided with an oil fill opening, placing a fixture in. said opening, connecting an air line to said fixture, delivering pressurized air through said fixture and into the interior of said cover, and cutting a hole in the wall of said cover in such manner that internal pressure within said cover ejects all chips from the hole during the cutting operation.

5. The steps of a method for drilling a hole in the intake manifold of an internal combustion engine equipped with a carburetor which comprises placing a fixture over the carburetor air inlet, connecting an air line to said fixture, delivering pressurized air into the interior of the manifold through said fixture, and drilling a hole in the wall of said intake manifold, said internal pressure ejecting all drill chips from the hole.

References Cited by the Examiner UNITED STATES PATENTS 1,522,102 1/ 1925 Cibelli 77-69 1,596,197 8/1926 Lindgren 77-69 2,515,260 7/ 1950 Pichler 77-42 2,547,986 4/1951 Van Dermark 29-427 3,071,991 1/1963 Ver Nooy 77-42 WILLIAM W. DYER, 111., Primary Examiner, FRANCIS s. HUSAR, Examiner. 

5. THE STEPS OF A METHOD FOR DRILLING A HOLE IN THE INTAKE MANIFOLD OF AN INTERNAL COMBUSTION ENGINE EQUIPPED WITH A CARBURETOR WHICH COMPRISES PLACING A FIXTURE OVER THE CARBURETOR AIR INLET, CONNECTING AN AIR LINE TO SAID FIXTURE, DELIVERING PRESSURIZED AIR INTO THE INTERIOR OF THE MANIFOLD THROUGH SAID FIXTURE, AND DRILLING A HOLE IN THE WALL OF SAID INTAKE MANIFOLD, SAID INTERNAL PRESSURE EJECTING ALL DRILL CHIPS FROM THE HOLE. 